[0001] The present invention relates to an inspection method for detecting the route of
leakage of fluid in places where no leakage of fluid should be produced such as piping
for liquid or gas, tank for liquid or gas, hull, window or body of automobile, house,
etc.
[0002] For example, in the piping of toilet or sink, it is often the case that leakage of
water is produced because of improper execution or deterioration due to aging, etc.
If there is any leakage of water, repairing is essential but the point of leakage
must be found before the repairing. The conventional method of detecting the point
of leakage consists in actually flowing water through the piping and carefully checking
the piping with the eyes of a well experienced expert.
[0003] However, in the case of any leakage of water, it is often the case that such leakage
takes place in piping installed in a dark and narrow place such as under the floor,
on the ceiling, inside a wall face, etc., and this makes it difficult to check the
point of occurrence of water leakage. Moreover, though there are cases where a leakage
is found at points easily recognizable by any person in the room, etc., the leak water
drops downward after flowing also in the horizontal direction under the ceiling or
along the ceiling or wall face. For that reason, finding the place where water drops
does not necessarily mean finding the very source of leakage of water and it is often
difficult even for an expert to find the exact point of leakage.
[0004] Moreover, even with water leakage at portions easy to observe from outside such as
water receiving tank, etc., a long time of observation is necessary to detect the
point of leakage in the case of a minimal leakage from pinhole, etc. and it is often
the case that, even if the point of leakage can be roughly spotted, it is difficult
to confirm the exact point of occurrence of water leakage. Especially with equipment
constructed by jointing a plural number of members, the leaking water naturally flows
through such points of jointing and, when leakage is produced at a plural number of
points, the water from all points of leakage gets together and passes through a single
route to eventually drip from a certain point, and this makes it very difficult to
accurately detect all the leak points. To be more in detail, water is generally colorless
and transparent and the amount of leak water is small. For that reason, even with
a long time of observation, it is often the case that no leakage is detected with
a leakage of several drops but detection becomes possible only when the leak water
from a plural number of points gathers together, so it is very difficult to accurately
detect all the leak points. As a result, just repairing one point is not enough to
stop the leakage and the inspection and repair work must be repeated a number of times,
requiring a long period of time and a large amount of repair cost for complete stopping
of the leakage.
[0005] Moreover, in structures such as building, house, etc., leakage of rain water is often
caused by poor execution or deterioration due to aging, etc. If there is any leakage
of rain water, it must be repaired, and the repair work must be preceded by detection
of the paint of leakage. For that reason, the method conventionally practiced for
finding such points of leakage of rain water is that a well experienced expert carefully
watches the structure on a rainy day.
[0006] However, if there is any leakage of rain water, the rain water penetrates to the
inside through gaps such as crack, etc. and flows downward through the structure.
For that reason, finding the point of dropping does not necessarily mean finding of
the exact paint of penetration to the inside of the structure, and it is very difficult
even for an expert to find the point of leakage of rain water. Especially, when the
penetration to inside takes place at a plural number of points, it is often the case
that the rain water which penetrates from a plural number of points flows along the
structure, gets together, passes through a single route and drops in the room, etc.
from a certain point, making it quite difficult to accurately detect all the leak
points. Therefore, in such a case, the leakage of rain water cannot be completely
stopped even if only one suspected point of leakage is repaired. As a result, the
inspection and repair work must be repeated a number of times, requiring a long period
of time and a large amount of repair cast for complete stopping of the leakage. The
present invention has been proposed in the light of the situation as described above
and its object is to provide an inspection method for detecting the route of leakage
of fluid at points of water leakage, etc. in the object matters to be inspected easily,
accurately and at low cost.
[0007] The present invention solves the above-mentioned problem by providing an inspection
method for detecting the route of leakage of fluid as set forth in claim 1.
[0008] An inspection method according to the present invention consists in preparing an
inspection liquid containing a light emitting material which emits light by being
irradiated with a beam such as ultraviolet ray, etc., applying the inspection liquid
to the object material to be inspected, and then irradiating a beam capable of illuminating
inspection liquid such as ultraviolet ray, etc. on the object material to be inspected
to illuminate the route through which the inspection liquid flowed so as to detect
the route of occurrence of any leakage of fluid in the object material to be inspected.
As object materials to be inspected, this method can be widely applied to such materials
as piping for liquid or gas, tank for liquid or gas, hull, window or body of automobile,
etc. having a space separated from others. Moreover, the present invention can also
be applied to the inspection of points of leakage of rain water or water in structures.
In the case where the object material to be inspected is a material having a portion
for storing water such as tank, etc., it may be all right to prepare an inspection
liquid containing a light emitting material by mixing said light emitting material
in this stored water.
[0009] In the present invention, the inspection liquid is applied to the object material
to be inspected. The method of application can be changed as required depending on
the structure of the object material to be inspected. It is all right to let flow
the inspection liquid inside the piping if the object material to be inspected is
a piping, pour the liquid inside the tank in the case of a tank, either float the
hull filled with the inspection liquid in a pool or fill the inside of the hull with
the inspection liquid if it is a hull, especially a small one, and flow the inspection
liquid from outside if the object material to be inspected is either windows or body
of automobile, for example. In the case of a structure, first the inspection liquid
is let flow instead of rain water from the rooftop of a house, for example, so that
it may flow down along the roof. As a result, if there is any point of leakage of
rain water somewhere in the roof, a part of the inspection liquid will penetrate into
the house through that point and pass through the back side of the roof to eventually
drop in the room.
[0010] Next, as a beam such as ultraviolet ray, etc. capable of illuminating a light-emitting
material is irradiated on the object material to be inspected, the route of occurrence
of leakage of fluid in the object material to be inspected emits light so that it
may be detected easily.
[0011] In this way, the detection of point of leakage can be made with emission of light
and this enables easy detection of even slight leakage. In the case of any leakage
of rain water, it is possible to draw the route of the inspection liquid from the
point of leakage of rain water to the point of dropping in the room.
[0012] Therefore, even when the leakage takes place at a plural number of points and the
water from those points gets together in to a single stream, the leakage can be detected
at the point in time when the leakage is produced at respective points of leakage
and the respective leak points can be spotted.
Brief description of the drawings:
[0013] Fig. 1 is an explanatory drawing of a case in which the inspection method of the
present invention is applied to a piping equipment.
[0014] Fig. 2 is an explanatory drawing of a case in which the inspection method of the
present invention is applied to a water receiving tank.
[0015] Fig. 3 is an explanatory drawing of a case in which the inspection method of the
present invention is applied to a small hull.
[0016] Fig. 4 is an explanatory drawing of a case in which the inspection method of the
present invention is applied to a structure.
[0017] An embodiment of the present invention will be explained concretely hereafter.
[0018] The inspection method for detecting point of water leakage in the object material
to be inspected of the present invention is a method which consists in applying a
prescribed inspection liquid to the object material to be inspected and then applying
ultraviolet rays to the object material to be inspected.
[0019] The inspection liquid is prepared by containing a light-emitting material which emits
light in reaction to at least ultraviolet rays. As this light-emitting material, there
is diaminostilbene type organic compound, for example. Diaminostilbene type organic
compound has such properties that it emits a blue-white light when irradiated by ultraviolet
rays but hardly emits any light with other beams, is harmless to human body and dissolves
in water at normal temperature. As product currently marketed for dyeing, there is
a product known under the commercial name of Illuminar BBS Conk (trademark of Showa
Kako K.K.) and an inspection liquid can be prepared easily by using this. In this
embodiment, Illuminar BBS Conk as sold in the market is diluted with water to 100
times the initial volume to be used as inspection liquid. By diluting it with water
to this volume, it becomes possible to make the liquid emit hardly any light unless
a prescribed quantity of ultraviolet light is irradiated on it and be almost invisible
in the normal slate when it is applied to the object material to be inspected.
[0020] As ultraviolet rays, a beam irradiated from an ultraviolet irradiation unit is utilized.
As this ultraviolet irradiation unit, a unit marketed under the commercial name of
Black Light (trademark of Matsushita Electric Industrial Co., Ltd.), for example,
is suitable as it irradiates a large amount of ultraviolet rays, and by using this
unit it is possible to enable sufficient emission of light even with an inspection
liquid diluted with water to 100 times the initial volume. While Black Light already
sold in the market is used as such ultraviolet irradiation unit for the sake of convenience
in the present embodiments, it may be replaced with any newly manufactured special
device or any existing unit as required.
[0021] A concrete inspection procedure of the present invention will be explained based
on Fig. 1 hereafter.
[0022] First, inspection liquid 1 is let flow from upstream (sink A1, in this case) of piping
A. As a result, the inspection liquid 1 flows through the piping A to the downstream
side. And, if there are any points of water leakage 3 ... 3 at cracks or joints on
the way of this piping A, part of the inspection liquid 1 flows out from such points
of water leakage 3 ... 3, flows to the back side of the ceiling B1 of the lower story
and further drops downstairs from the back side of the ceiling B1. B2 indicates the
floor of the story in which a sink A1 is provided. At that time, the flowing inspection
liquid 1, which is prepared by sufficiently diluting a light-emitting material with
water, hardly emits any visible light in the normal state. Therefore, the inspection
liquid 1 is invisible from outside and does not spoil the appearance even if it is
not washed away and can therefore be left as it is.
[0023] Next, ultraviolet rays are irradiated on the piping A from the back side of the ceiling
B1 by means of a Black Light as ultraviolet irradiation unit 2. This makes it possible
to visualize the route through which the inspection liquid 1 flowed because the inspection
liquid 1 sticking to the piping A emits a blue-white light. Therefore, by following
the route through which the inspection liquid 1 flowed, the points of water leakage
3 ... 3 can be easily detected.
[0024] In the case of a piping, presence of a leakage is found usually with dripping of
water to downstairs and then inspection is started. At that time, by flowing the inspection
liquid 1, in the state where ultraviolet rays are irradiated from the ultraviolet
irradiation unit 2, at portions where the points of water leakage 3 ... 3 are suspected,
it becomes possible to detect such points at a stage where only a small amount of
the inspection liquid 1 leaks from the respective points of water leakage 3 ... 3.
Therefore, the respective points of water leakage 3 ... 3 can be confirmed individually
and accurately. Moreover, in the case where the leakage was detected in the state
where the leakage of the inspection liquid 1 of a plural number of routes from the
respective points of water leakage 3 ... 3 gets together, the respective points of
water leakage 3 ... 3 can be confirmed accurately by once wiping off the inspection
liquid 1 of that route of confluence and then flowing the inspection liquid 1 again
in the state of irradiation of ultraviolet rays.
[0025] Fig. 2 indicates a case where the object material to be inspected is a water receiving
tank C. The detection of leakage can be made by filling the inside of the tank C with
the inspection liquid 1 and irradiating ultraviolet rays on the inspection liquid
1 flowing out from the point of water leakage 3 by means of the ultraviolet irradiation
unit 2. In that case, the inspection liquid 1 may be prepared outside the tank C as
in the embodiment explained earlier but, if water is stored in this tank C, the inspection
liquid 1 may also be prepared by using this water. Namely, the water stored in the
tank C can be changed into inspection liquid 1 by injecting a light-emitting material
in it. To be more concrete, the stock solution of said Illuminar BBS Conk (trademark
of Showa Kako K.K.) may be injected in the water stored in the tank C in a volume
equal to approximately one hundredth of the water volume.
[0026] Fig. 3 indicates a case where the object material to be inspected is a small hull
D. Fig. 3 (A) represents a case where the hull D is floated in a pool E filled with
the inspection liquid 1 and ultraviolet rays are irradiated, by means of the ultraviolet
irradiation unit 2, on the inspection liquid 1 leaking inside the hull D from the
point of water leakage 3, for verification. Fig. 3 (B) is a case where the hull D
is filled with the inspection liquid 1 and ultraviolet rays are irradiated, by means
of the ultraviolet irradiation unit 2, on the inspection liquid 1 leaking to outside
the hull D from the point of water leakage 3 for verification.
[0027] Fig. 4 shows an example of applying the present invention to a structure, especially
a wooden house, where the inspection liquid 1 is let flow from the rooftop of the
house F. This makes the inspection liquid 1 flow along the roof to the lower part
of the roof. And, if there are any points of leakage of rain water 3 ... 3 in the
upper, middle, or lower parts of this house F, part of the inspection liquid 1 penetrates
into the back side of the roof F1 from such points of leakage of rain water 3 ...
3 and also flows from the back side of the roof F1 along the strut F2 and the tie
beam F3 to reach the ceiling F4. At that time, because the inspection liquid 1 that
is flowing is prepared by sufficiently diluting a light-emitting material with water,
hardly any emission of light can be detected in the normal state. Therefore, the inspection
liquid 1 is invisible from outside and does not spoil the appearance even if it is
not washed away and can therefore be left as it is on the roof. In the case of a wooden
house, leakage of rain water is liable to be frequently produced at the valley of
a so-called hip roof, but the case of an ordinary roof is explained here for the sake
of convenience. Therefore, in the case of an wooden house having hip roof, the inspection
work may be executed effectively if the inspection liquid 1 is let flow mainly in
the valley of the hip roof.
[0028] Next, ultraviolet rays are irradiated on the strut F2 and the tie beam F3 with Black
Light as ultraviolet irradiation unit 2 from the back side of the roof F1. This makes
the inspection liquid 1 flowing along the back side of the roof F1, etc. emit a blue-white
light to visualize the route of passage of the inspection liquid 1. Therefore, by
tracing this passage through which the inspection liquid 1 flowed, it is possible
to detect the points of leakage of rain water 3 ... 3 easily and accurately.
[0029] While explanation was given on the case of a wooden house in this embodiment, the
present invention can be adapted to a variety of structures made of mortar or concrete,
etc. In a mortar or concrete structure, it is known that leakage of rain water often
takes place at portions where a metallic fence or an aluminium window frame are provided.
However, it is not easy to elucidate from which point the rain water comes in and
by which route it flows to the inside of the structure. So, by flowing the inspection
liquid of the present invention to such parts and visualizing the route of penetration
of the inspection liquid with irradiation of ultraviolet rays, the point and the route
of penetration can be clarified. Moreover, by visualizing the route of penetration,
it also becomes possible to judge if the penetration comes from a crack or if it is
caused by deterioration, and take accurate remedial measures.
[0030] In addition, though no illustration is made, for automobile body, window glass, and
gaps between automobile body and window glass, etc., the detection of leakage can
be made by flowing the inspection liquid from outside the car body and irradiating
the inspection liquid leaking inside with ultraviolet rays. Moreover, while leakage
of liquid such as water, etc. was taken as target of detection in the embodiment,
the present invention can also be applied to piping and tank, etc. of gases. Furthermore,
it is applicable to not only equipment of household use such as toilet piping, fish
tank, etc. but also to external and internal pipings, drainage facilities of bridge
for highway, etc. Still more, it is also all right to apply the inspection liquid
on the object material to be inspected under pressure such as discharging the inspection
liquid at high pressure, etc. by connecting a pump to the tank storing the inspection
liquid. Yet more, in a narrow place, it will be all right to attach a camera or a
video camera at the tip of a long body (preferably a bendable one) to observe and
record the state of emission of light of the inspection liquid in the object material
to be inspected. At that time, the irradiation unit for irradiating beam such as ultraviolet
rays, etc. can be attached to the tip of another or the same long body. It is also
possible to lead the ultraviolet rays, etc. of the irradiation unit placed at a distant
position by means of optical fibers and lead the state of emission of light of the
inspection liquid to the camera or video camera at hand with optical fibers. It is
further possible to connect a compact camera which can be introduced in a narrow place
and a monitor at hand by means of a cable.
[0031] As described in the embodiment given above, the present invention, which consists
in applying an inspection liquid to the object material to be inspected, and then
irradiating ultraviolet rays on the object material to be inspected to illuminate
and visualize the route of passage of the inspection liquid, makes it possible for
anybody, even if he is not an expert, to find points of leakage of water or rain water,
etc. easily and accurately and take the necessary remedial measures accurately. In
addition, such inspection work can be performed easily and at low costs. As described
above, the present invention has succeeded in providing a useful and practical inspection
method for finding points of leakage of fluid easily and accurately.
1. An inspection method for detecting the route of leakage of fluid on an object, comprising
applying to the object an inspection liquid which emits light when irradiated with
a given type of radiation, irradiating the object with the said radiation, and detecting
light coming from the object so as to detect the route of any leakage of the inspection
liquid.
2. An inspection method as claimed in claim 1, wherein the object delimits a space separated
from others, the object being, for example, piping for liquid or gas, a tank for liquid
or gas, a hull, a window, or the body of an automobile.
3. An inspection method as claimed in claim 1 or 2, wherein the object material comprises
means for storing water, such as a tank, and the inspection liquid is prepared by
introducing into the stored water a substance which emits light when irradiated by
the said radiation.
4. An inspection method as claimed in claim 1, wherein the object is a building structure
and the inspection is made to detect points of leakage of water or rainwater in the
structure.
5. An inspection method as claimed in any preceding claim, wherein the said radiation
is ultraviolet light.
6. An inspection method as claimed in any preceding claim, wherein the inspection liquid
is clear and colourless.